A remote code execution vulnerability exists in the way that the Microsoft Server Message Block 3.1.1 (SMBv3) protocol handles certain reque
A remote code execution vulnerability exists in the way that the Microsoft Server Message Block 3.1.1 (SMBv3) protocol handles certain requests, aka 'Windows SMBv3 Client/Server Remote Code Execution Vulnerability'.
- Published
- Mar 12, 2020
- Updated
- Aug 12, 2026
- EPSS
- 99.8% · 100th percentile
- CWE
- CWE-119
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Report tools
Action score
100
Now
Patch today or shut off access.
- CVSS
- 40 / 40 · 10.0 / 10
- CISA KEV
- 30 / 30 · Listed
- EPSS
- 30 / 30 · 99.8%
CISA SSVC decision
- Exploitation
- active
- Automatable
- yes
- Technical impact
- total
Vulnrichment: CISA's decision-tree inputs.
Actively exploited in the wild
CISA added this to its Known Exploited Vulnerabilities catalog on Feb 10, 2022. That signals real attacks, not theory.
Remediation deadline for government agencies: Aug 10, 2022.
Known to be used in ransomware campaigns.
Affected systems
| Vendor | Product | CPE |
|---|---|---|
| microsoft | windows 10 1903 | cpe:2.3:o:microsoft:windows_10_1903 |
| microsoft | windows 10 1909 | cpe:2.3:o:microsoft:windows_10_1909 |
| microsoft | windows server 1903 | cpe:2.3:o:microsoft:windows_server_1903 |
| microsoft | windows server 1909 | cpe:2.3:o:microsoft:windows_server_1909 |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- microsoft windows server 1903all versions
- microsoft windows server 1909all versions
Versions reported by the vendor
Affected version ranges reported by the assigning authority (microsoft). Independent of NVD's CPE analysis and usually ahead of it.
Microsoft Windows 10 Version 1903 for 32-bit Systems
- unspecifiedaffected
Microsoft Windows 10 Version 1903 for ARM64-based Systems
- unspecifiedaffected
Microsoft Windows 10 Version 1903 for x64-based Systems
- unspecifiedaffected
Microsoft Windows 10 Version 1909 for 32-bit Systems
- unspecifiedaffected
Microsoft Windows 10 Version 1909 for ARM64-based Systems
- unspecifiedaffected
Microsoft Windows 10 Version 1909 for x64-based Systems
- unspecifiedaffected
Microsoft Windows Server, version 1903 (Server Core installation)
- unspecifiedaffected
Microsoft Windows Server, version 1909 (Server Core installation)
- unspecifiedaffected
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
No fix version is recorded for this entry. Check the references for vendor advisories.
Exploit status
Weaponized
A ready exploit tool or active in-the-wild use is known for this vulnerability. This should be your top priority.
Evidence
- Metasploit module ×2
- Exploit-DB entry ×3
- Nuclei detection template ×1
- Proof-of-concept repository on GitHub ×50
Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.
| Source | Kind | Date |
|---|---|---|
| Exploit-DB entry | dos | 2020-03-14 |
| Exploit-DB entry | local | 2020-03-30 |
| Exploit-DB entry | remote | 2020-06-02 |
| Metasploit module | exploit/windows/local/cve_2020_0796_smbghostSMBv3 Compression Buffer Overflowexploit | 2020-03-13 |
| Metasploit module | exploit/windows/smb/cve_2020_0796_smbghostSMBv3 Compression Buffer Overflowexploit | 2020-03-13 |
| Nuclei detection template | Nuclei template CVE-2020-0796 | — |
| Proof-of-concept repository on GitHub | stars:53 | 2019-11-19 |
| Proof-of-concept repository on GitHub | stars:18 | 2020-03-10 |
| Proof-of-concept repository on GitHub | stars:9 | 2020-03-11 |
| Proof-of-concept repository on GitHub | stars:28 | 2020-03-11 |
| Proof-of-concept repository on GitHub | stars:722 | 2020-03-11 |
| Proof-of-concept repository on GitHub | stars:14 | 2020-03-11 |
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
- First PoC-115 d
- Published
- Metasploitsame day
- CISA KEV+699 d
- TodaySep 29, 2026+2392 d
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- high · data can be read
- Integrity
- high · data or configuration can be modified
- Availability
- high · the service can be disrupted
Impact can extend beyond the vulnerable component (scope changes).
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Changed
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- High
Weakness class (CWE)
CWE-119 · Improper Restriction of Operations within the Bounds of a Memory BufferCVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
- Buffer Overflow via Environment VariablesCAPEC-10likelihood: High · High
- Overflow BuffersCAPEC-100likelihood: High · Very High
- Buffer ManipulationCAPEC-123likelihood: High · Very High
- Client-side Injection-induced Buffer OverflowCAPEC-14likelihood: Medium · High
- Filter Failure through Buffer OverflowCAPEC-24likelihood: High · High
- MIME ConversionCAPEC-42likelihood: High · High
- Overflow Binary Resource FileCAPEC-44likelihood: High · Very High
- Buffer Overflow via Symbolic LinksCAPEC-45likelihood: High · High
ATT&CK techniques
—
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for all 385,000+ vulnerabilities; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for helpChange log
No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.
References
- packetstormsecurity.com/files/156731/CoronaBlue-SMBGhost-Microsoft-Windows-10-SMB-3.1.1-Proof-Of-Concept.html
- packetstormsecurity.com/files/156980/Microsoft-Windows-10-SMB-3.1.1-Local-Privilege-Escalation.html
- packetstormsecurity.com/files/157901/Microsoft-Windows-SMBGhost-Remote-Code-Execution.html
- packetstormsecurity.com/files/158054/SMBleed-SMBGhost-Pre-Authentication-Remote-Code-Execution-Proof-Of-Concept.html
- portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-0796
- www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-0796
Vendor advisories and official records. Exploit/PoC links are deliberately left out.